1. Technical Field
The present disclosure relates to a headlamp control device and a vehicle headlamp having the headlamp control device.
2. Related Art
Currently, a so-called Adaptive Front-lighting System (AFS) is developed which can obtain an appropriate visualizing performance by changing an irradiation range of a headlamp in accordance with a driving environment. This system is configured to move the irradiation range of the headlamp in a transverse direction in accordance with a steering amount of a handle or to change the irradiation range of the headlamp based upon whether a vehicle is traveling in a city or on a highway.
In addition to the AFS, the vehicle headlamp is generally capable of selecting a low beam or a high beam. The low beam is used to illuminate a near area with a certain light intensity, and a light distribution regulation is determined so as not to cause glare to an oncoming vehicle or a preceding vehicle, where the low beam is mainly used upon traveling in the city. On the other hand, the high beam is used to illuminate a forward broad range and a far position with comparatively high illumination, and is mainly used upon traveling a road where few oncoming vehicles or preceding vehicles exist. Accordingly, the high beam improves the visualizing performance enabling a driver to more easily see a visual object compared with the low beam, but may cause glare to a pedestrian or a driver of a vehicle existing in front of the vehicle.
For this reason, a technology for changing a light distribution in the range of the high beam has been proposed. JP-A-2008-37240 describes a related art vehicle head lamp which turns off a high beam unit, which is illuminating a high beam irradiation area that has an irradiation prohibition object therein, among a plurality of high beam units.
In addition, in the case where a vehicle selecting the high beam causes glare to the driver of the preceding vehicle traveling in front of the vehicle, a degree of the glare changes in accordance with a distance. For this reason, JP-A-2000-233684 and JP-A-H07-101291 describe a headlamp device which suppresses glare by moving a cutoff line or controlling luminance of a lamp in accordance with the position of the preceding vehicle.
In order to prevent a traffic accident between the vehicle and a pedestrian, it is important for the driver of the vehicle to be able to accurately check for the existence of the pedestrian. However, the above-described technologies are contrived from the viewpoint of reducing the glare influencing the pedestrian or the driver of the vehicle, and the improvement of the visualizing performance enabling the driver to see a pedestrian or other potential trouble area or object or the like is not considered.